Centre Bore Modifications
When fitting aftermarket wheels or swapping OEM alloys between different vehicle manufacturers, one of the most critical structural measurements is the wheel’s centre bore. The centre bore must match the vehicle’s hub lip perfectly to ensure a “hub-centric” fitment, where the weight of the vehicle is supported safely by the hub rather than the wheel bolts or studs alone.
If your chosen alloy wheels have a centre bore that is too small for your vehicle’s hub, trying to force them on or using unsafe spacer configurations is incredibly dangerous.
At TT Precision, we provide expert alloy wheel centre bore modifications using our advanced, computer-controlled CNC machinery. We can safely machine and enlarge the internal diameter of your wheel’s centre bore to exact tolerances, allowing for a flawless, secure, and vibration-free fitment on your vehicle.
The Engineering Behind Hub-Centric Accuracy
Modifying the centre bore of an alloy wheel is not a task that can be achieved safely with hand tools, sanding drums, or standard workshop drills. Even a fraction of a millimetre of misalignment will cause the wheel to sit off-centre, leading to severe steering wheel vibrations, premature tyre wear, and dangerous stress on your wheel bearings.
Our precise machining process guarantees absolute concentricity:
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True-Axis Setup: The alloy wheel is securely mounted and clocked onto our specialised CNC machinery, ensuring it is perfectly centred relative to the wheel’s original rotating axis.
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Digital Measurement: We measure the existing bore and calculate the precise micron (µm) tolerances required to match your new vehicle hub profile perfectly.
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Clean Boring & Chamfering: Our precision cutting tools cleanly machine away the excess aluminium alloy, widening the bore smoothly. We then cut a flawless rear chamfer (bevel) to ensure the wheel slides seamlessly over the radius of your vehicle’s hub lip.
Why Choose TT Precision for Custom Bore Machining?
As professional precision engineers, our technical expertise sets us apart from standard alloy wheel cosmetic refurbishment shops:
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Absolute Structural Integrity: We carefully inspect the wheel casting beforehand to ensure there is sufficient structural material to safely support the enlargement without compromising the structural safety of the wheel face.
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Micron-Perfect Tolerances: Our CNC machining setups eliminate human error, ensuring that the new bore is perfectly round and completely centred with the wheel’s bolt pattern (PCD).
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Elimination of Steering Vibration: By achieving a true hub-centric fitment, you entirely eliminate the high-speed wheel balancing issues and vibrations common with poorly fitting wheels.
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Bespoke Fitting Solutions: Whether you are fitting classic wheels to a modern chassis, adapting motorsport alloys, or altering custom wheels for a unique project car, we provide a reliable engineering solution.
Centre Bore Machining Technical Capabilities
Our engineering workshop is fully equipped to handle a comprehensive range of custom wheel modifications:
| Modification Service | Engineering Detail | Typical Application |
| Bore Enlargement | Machining standard OEM bores to larger diameters | Fitting VW/Audi wheels onto Mercedes hubs. |
| Spigot Ring Pocketing | Machining a precise step/recess into the back of the wheel | Creating a secure seat for custom hub-centric spigot rings. |
| Face & Offset Skimming | Milling material off the mounting face | Altering the wheel’s offset (ET) to clear brake calipers or arches. |
| Concentric Chamfering | Re-cutting the rear mounting bevel | Ensuring flush fitment against the vehicle hub assembly. |
Trusted Machining for Specialists and Enthusiasts
Whether you are an automotive restoration specialist executing a custom hub swap, a wheel distributor needing batch modifications, or a car enthusiast building a unique custom project, TT Precision provides the elite engineering infrastructure you require.
We treat your high-value alloy wheels with the exact same precision and quality control principles that we apply to our complex industrial and aerospace engineering contracts.
Get a perfect, vibration-free fitment. Contact the engineering specialists at TT Precision today to discuss your centre bore modification requirements or to request a quote.
Quality, Safety & Engineering Excellence
With years of precision engineering expertise, TT Precision Engineering Limited combines technical knowledge with industry-leading machinery to produce consistently high-quality results. Every wheel is handled with care and machined using calibrated CNC equipment to ensure strength, symmetry, and long-term durability.
When it comes to centre bore modifications, accuracy is everything — and that’s exactly what we deliver.
Frequently Asked Questions
What is a wheel’s centre bore? The centre bore is the hole in the middle of the wheel that fits over your vehicle’s hub. For a hub-centric fit it must match the hub lip, so the hub supports the weight of the vehicle rather than the wheel bolts or studs alone.
Can a centre bore be made larger? Yes. We machine and enlarge the centre bore on CNC machinery to exact tolerances, after checking the wheel casting has enough material to support the enlargement safely.
Can a centre bore be made smaller? No. Machining can only remove material, so a bore that is larger than your hub is filled with a hub-centric spigot ring instead.
Why can’t a centre bore be opened up with hand tools? Even a fraction of a millimetre of misalignment will make the wheel sit off-centre, causing steering vibration, premature tyre wear and extra stress on the wheel bearings.
Who do you machine centre bores for? We work with automotive restoration specialists, wheel distributors needing batch modifications, and car enthusiasts building custom projects.
How do I get a quote? Contact us with details of your wheels and the vehicle they will be fitted to, and we will be happy to discuss your requirements.
Custom Wheel Enquiries
For truly bespoke wheel customisations that go beyond our standard services, we’re ready to help. Whether it’s a one-of-a-kind design or specialised machining, contact us to discuss your requirements and create the ideal solution for your vehicle.
Please GET IN TOUCH… We will be happy to discuss your requirements.
